Flexible shaft-coupling.



No. 628,!26. Patentad July 4, |899.A

H. F. SHAW. FLEXIBLE-SHAFT CUUPLlNG.

(A'ppliction med .my 1e, 1898i) (No Modl.)

Inn/SNTE" j 6MM MTNEIESES:

UNITED STATES" PATENT OFFICE.

HENRY E. SHAW, or BOSTON, MASSACHUSETTS.

FLEXIBLE SHAFTCOUPLING.

sPEcIFIcATIoN forming part of Letters :Patent No. e2s,12e, dated .my 4, 1899.

Application filed July 16, 1898. Serial No. 686,136; SNO mdel.)

To all whom it may concern.-

Be it known that I, HENRY F. SHAW, of Boston, in the county of Suffolk and State of Massachu setts,have invented certain new and useful Improvements in Flexible Shaft-Couplings, of which the following is a specification.

This invention has relation to couplings for transmitting power between unaliued shafts;

and its object is to provide a coupling hav- The head or end of each shaft ing considerable rigidity or resistance to torsional strain and one which will allow of 'a certain amount of adjustment of the shafts.

The invention consists in the novel features of construction and arrangement which I shall now proceed to describe and claim...

Of the accompanying drawings, forming a partnf this specification. Figure l represents a perspective view of a shaft-coupling constructed in accordance with my invention. Fig. 2 represents a top'planview thereof with the shaft-bearings in section. Fig. 3 represents an elevation. Fig. 4 represents a'section on line 4-4 of Fig. 2. Fig. 5 represents a sectional plan view showingan application of my invent-ion.

The same reference characters indicate the same par-ts in all the gures.

Referring to the drawings, a and b designate two shafts mounted, in the .present instance, at right' angles to each other and housed in suitable bearings a a', which prevent longitudinal movement of the shafts. is l bif u rcated or formed with ears a2 a2 b2 b2, between which end links c d are pivoted on pintles c df. 'le is a link pivoted to one end of the end link c and having a bifurcated end which embraces said link and supports a pintle c', passing through an aperture in the link c. The other end of the link e. is connected with the link d by 'means of two 1ink-plates f f, supporting pintles f f2, which extend through apertures in the end links e and d, respectively. The parts eff constitute intermediate links.

When a torsional either of the shafts a or b, the' motion is transmitted through the four links c, e, ff, and d and the connecting-pintles of the couplings to the other shaft, which is. thereby rotated. The full lines in Fig. 2 show a position of the links e f at'onepointin the revolution of the sary in order that the ficient strength to effect the rotation of the or rotary motion is given shafts, andthe dotted lines show the position of said'links when the shafts are turned In passing from one of these positions tothe other the links c d turn on 'the pintles c' d', and the distance between the alternate ends of the' pin'tles e' f 2, alternately increases and decreases, said i pintles c' and d', on which the links c d turn or swing. This variation of distance between the ends of the pintles e' f2 is compensated for by the described arrangementof the links and pintles, said arrangement permitting a lateral flexure ofthe couplingin'any direction, so that jUhevariations in distance above. referred are compensated for. Without `such compensation the shafts, when confined against endwise movement, could not rotate freely. f As abovek mentioned, the link connections ef are adapted to yield laterally. This construction compensates for the approach toward and recession from each other of the ends of the pintles e'f2, and thus permits of the use of pint-les oi uch length as is necesdevice may possess suf- 'd-riven shaft even when'there is considerable resistance thereto, as in the case of the driven Wheel of a bicycle when hill-climbing. The longer the construction of the pintles and the lesser the number employed the greater is the strength of the coupling. It is obvious'I that with a large number of links the wear is greater and the strength is less, and there is liability of a twisting or torsionaleifect, having a tendency to draw or force one of the shafts longitudinally, and when the pint-les employed are very short the leverage about the axis of rotation is reduced, as is obvious.

My invention has many usef n1 applications which -need not be individually illustrated or described.

Fig. 5 represents the invention as applied to the propulsion of a bicycle. g is a spurgear on the crank-shaft g of the bicycle, and h is a spur-pinion on a parallel shaft h. are .two shafts extending through the lower frame-bars i' i" of the bicycleon either side of the rear wheelj. The shafts i z' are connected with the ends of the shaft 71 by means through ,a half-revolution from said point. Y

pintles being offset from the ICO of my improved exible coupling, and similar couplings may be used to connect the rear ends of the shafts e' with the hub of the rear wheel. Upon turning the crank-shaft g in a forward direction the pinion h' i's rotated an opposite direction, and in passing throng the couplings and the shafts-tithe motion is reversed and the rear wheel is revolved in a forward direction.

I am aware that flexible couplings have been constructed in which the equivalents of the links or blocks c d have been employed and a'single link used to connect said links. In this form of coupling, however, the distance between the ends of the shafts cannot be varied even slightly without greatly increasing the running;r friction of the coupling. My. improved coupling overcomes this objection,=since it isobviousthat the two links e zo,j`,pivoted.together at f', will allow of some variation in the distance between the ends of `the shafts a b. This feature is important in allowing the shafts .to be adjusted in their bearings.

Iclaim- A-`coupling for unalined shafts, comprising a pivot at the end of each shaft, a block con- -nected with each pivot and free to oscillate only in a plane at right angles to said pivot, and laterally-yielding link connections forming the sole means for connecting the two blockssaid link connections being pivoted against exure in one direction and yielding in the direction of a plane at a. right angle to the plane of oscillation of said pivoted blocks.

signature in presence of two witnesses.

HENRY F. SHAW. Witnesses:

.A. D. HARRISON,

C: F. BROWN.

to the first-mentioned pivoted blocks and rigid In testimony whereof I have' aixed my 

